[Elecraft] KPA100 - Low Voltage output from High Voltage Bias Supply Circuit

[Don Wilhelm]

Michael,

You said the 'magic words' - HI CUR, Hi REFL messages and lack of power 
control (other than low and high power selection) *after* a lightning storm.

That is an indication that the lightning surge zapped diodes D16 and D17 
in the KPA100 wattmeter - the result is that the base K2 microprocessor 
*thinks* there is no power output and increases the drive until it 'runs 
out of gas' - the K2 will produce max power output under those conditions.

Replacement of D16 and D17 is in order as a first step.  If that does 
not cure things, then we can help you troubleshoot it further.

73,
Don W3FPR

Michael Haygood wrote:
> Hi,
> 
> I've been using my K2/100 for many months with great results.  After a 
> recent storm containing lightning the next time I fired up the K2/100 I 
> received the "HI CURR" message and the "HI REFL" messages upon initial 
> transmit.  This was unusual, so the next thing I did was consult the 
> troubleshooting guide in the KPA100.
> 
> Using a wattmeter and connected to a dummy load, I measured the output 
> power of the K2/100 with the power outupt contol set to less than 11 
> watts and noticed that for a setting of 5 watts the output of the K2/100 
> was about 10 watts.  For a power output setting of 15 watts, the output 
> was very high - about 100 watts.
>